Darren is *not making*any more at the moment, but will pick up production as soon as he's finished improving the build-time to better keep up with future orders.
Hey, man! You don't need any extra fuel... you're running rich enough already!!
On OLDER REGULATORS WITH THE HOSE BARB FITTINGS,
On NEWER REGULATORS WITH O-ring fittings, instead of hose barbs, like on my '89's, You can just use sockets on both sides of the reg, and don't have to make the home made pipe / jig.
If you want to set your new pressure exactly, hook a rubber tube from a pressurized air tank to the side fuel fitting that's sticking out of your homemade pipe/jig, add a gauge to the line with a tee, and SLOWLY crack open the air tank valve. You want it barely cracked open, otherwise you'll let the pressure out of the tank too fast, and get a false reading. The pressure will rise to a point, then begin leaking out of the reg, and will rise no more. You'll hear the air hissing out, and the pressure will stay at the same point. That point should be 55 psi before you squeeze the reg in the vise.
An alternative to the vise is to stand the assembly on a hard surface, and tap the top chromed socket with a hammer. Don't go wild with the hammer!
Remember that injectors can be
damaged by pressures more than 75 psi over boost, and that you must have a good
enough pump & filter to keep the pressure high under WOT. Having 65 psi over
boost at 5 lbs of boost is no good if you have only50 psi over boost at 20 lbs
of boost. The pump's got to be healthy enough to STAY at 65 over boost at all
boost levels. A clean filter is a must.
Just check your fuel pressure at WOT, under boost, to see if the pressure remains the same amount over boost.
Try JamesRichardson, of Canada. Price is in the $55 area.
He does excellent work.
just send him a healthy regulator, and you do no work; it comes back ready to
rock and roll.
|Fuel pressure||45 PSI||40 PSI||35 PSI||30 PSI|
|Flow of 52 pph "+40% injectors"||47 pph||44 pph||42 pph||38 pph|
|Flow of 42 pph "+20% injectors"||38 pph||36 pph||34 pph||31 pph|
Example#1: Let's say that you have 27
pph T1 injectors, and you want to upgrade for big power in the future. You
can run42 pph (+20% injectors) units at 30 psi, and they'll act like 31 pph
When you raise the fuel pressure to just 35 psi, with your pump still *loafing*, you'll have the flow ofT2 injectors.
Example #2: You have stock 33 pph T11 injectors, and you swap for +20% injectors. Run 40psi fuel pressure, and they flow like 36 pph units. Roughly 10% over normal, which is easy for your computer to idle clean & smooth.
Example#3: You have stock 33 pph T11 injectors, and you swap for +40% injectors. Run 30 psi, and you get 38pph injectors, which is a big improvement over stock.. People often question the quality of the spray pattern at 27 psi, which I run. I can only tell you that I get good gas mileage and pass emissions with those big 52pph units running at 27 psi. Other car companies run their fuel pressures way below our stock55 psi.
In any of the above examples, you can now go to a few more pounds of boost before leaning. When you raise boost above the "leaning" point, it's time to raise your fuel pressure.
Of course, the hot trick is to get the fuel pressure to rise all by itself, whenever it's needed.
3.Gettingthe pressure to rise on it's own, as you need
You can gradually close off the return line as the boost rises with an adjustable gain regulator.
The way Slug runs is with an adjustable gain regulator.
CARTECH is selling this adjustable gain regulator for $209, plus shipping. This model is number 20002. It is fully adjustable from 1-7 psi of fuel pressure per pound of boost. My car likes 3:1 gain; your car might like 2.5:1, or 4.1:1. No problem!
Remember that we're dealing with high fuel
pressures, and therefore need fuelinjection fuel hose. Normal fuel
hose is much weaker than F.I. hose.
Here's a sample of how the fuel curve works on a car running big injectors with 30 psi fuel pressure and a 3:1rate on the rising gain regulator:
4. Extra injectors.
My second favorite technique, and also the cheapest, is to add extra injectors.($20- $40 per set of junkyard injector, new pressure switch, and "tee" with fuel line.) Pressure switches turn them on as needed, and your car runs a totally stock fuel system when you're not at WOT, so gas mileage and emissions are unaffected.
DarrenDawes is selling pressure activated switches.
COLD START INJECTORS: You can
look at old VW's and Saabs in your local junkyard. On the intake manifold you'll
see that there are 4 injectors neatly in a row, and one more injector all by
itself. The lone injector is the cold start injector .Cut off the fuel line with
snips or cutters, and unbolt the two little bolts on the injector flange. It
lifts right out, with no effort.
There's a banjo fitting on the top of these Bosch injectors. Leave it on, and leave the first couple inches of hard skinny fuel line on the banjo fitting. You can slip 3/16ID fuel hose right over the 2 inches of line already on the injector, and clamp it on.
To supply fuel, you'll need to get brass fittings from NAPA to make a "tee" that has 5/16" hose barbs on each end, with a 3/16 nipple in the middle.
You splice the tee into the rubber fuel line that feeds your fuel rail. I use 3/16" rubber fuel line to run from the tee to the injector. You can use metal line if it makes you feel better. Then connect the metal lines with short pieces of 3/16" fuel line and clamps.
will note that there's a vacuum line barb on the switch. These switches DON'T
LIKE vacuum! Use a pressure source that doesn't see vacuum. Use an intercooler
tube; epoxy a small vacuum line barb on it.
...Or use the intake manifold for a source, but put in a one-way (check)valve so that it doesn't see vacuum. Then install a tiny pinhole vent to atmosphere between the check valve and the pressure switch (about .015"to .020")
The switch will work on higher boost when the adjustment screw is turned clockwise; it will work at lower boost when the screw is turned counter-clockwise.
The polarity of the 2 injector wires doesn't matter; it'll work no matter which color wire goes to positive. Send one wire directly to positive, and have a pressure switch send ground to the injector at 14 psi or so.
Watch your rich-lean gauge; keep about .9V on the gauge. If you don't have one, get
one. Go to DawesDevices for a great
Don't have it come on early unless your rich-lean gauge tells you it's needed. (less than .9V) The extra injector will allow a few more psi of boost. That's when you really feel the difference.
Flow rates of these injectors
commonly support either 15 (usually the VW units) or 30 HP (usually the Saab units). Apply 12 volts to click them open, then blow through
ones that are slightly harder to blow through are good for 2 psi more boost (15
HP) The injectors that are slightly easier to blow through are good for 4 psi
more boost (30 HP) Strangely, the ones with the smaller looking
injector holes flow more, and are the "30 hp" units. These seem to be mainly in